A large number of phenotypically and genotypically distinct neurodegenerative disorders are characterized by the accumulation of proteinacious, and often fibrillar aggregates and these aggregates are the defining neuropathologic features of many neurodegenerative disorders. While frontotemporal dementia (FTD) is a relatively well-defined clinical disorder, the neuropathology of FTDs is evolving at a rapid pace and is far from well delineated at this time. Indeed, the clinically defined FTD syndromes are associated with multiple neuropathologically defined disorders, but these relationships remain ill-defined and incompletely characterized. Thus, a thorough postmortem examination of subjects with FTD is essential to further refine the clinicopathologic correlation in these patients as well as provide material for the elucidation of molecular mechanisms of disease. Thus, the growing cohort of FTD patients followed in Project 1 in this Program Project Grant (PPG) and the increasing number of postmortem brain samples in need of characterization and study in this PPG mandates inclusion of a Neuropathology Core. The Neuropathology Core supports the overall goals of this PPG by providing diagnostic neuropathology, brain and biological sample banking, database tracking of samples and neuropathology data on all frontotemporal dementia (FTD) subjects followed in Project 1 of this PPG. In addition, the Core provides advice and consultation to all PPG investigators, nearly all of whom utilize human biological samples.